Repeating tasks and reminders

Ideally this task is done some time on Sunday evening though the exact time is not important and it is not a disaster if it overruns into Monday, hence the repeating task rather than a calendar entry.

I can set the task with a start date/time and due date/time which means it appears in my task list at the right time and with a reminder set some time before the due time which then reminds me at a good time. I can also set this to repeat weekly.

The problem comes when, for some reason, I am prevented from doing the task on Sunday evening and it has to be done on Monday instead. If I change the due date/time in order to get re-reminded some time on Monday this new date/time is used for the next task in the repeating series once I complete the current task which is not what I want.

As an alternative I can set the task to repeat "Every Sunday" but this seems to fix the time component of the start and due date/time to 1200 which is also not what I want.

Is there any way to say repeat "Every Sunday at 18:00" or some such thing? I tried that but it didn't seem to work but maybe I have just got the wording wrong. Is there any other way to do what I am trying to do?

You can have it repeat "Every Sunday" by using the advanced repeating option, but there isn't a way to have the time for the next task to be different from the previous task. If you are changing the times to get re-reminders, then the newest time you pick will be what is kept for the next version of the task. We don't yet have a way to make an edit to a repeating task that only applies to that instance of the repeat. All edits affect all versions of the repeating task.